What is a good source for reviewing employers to know whether the company is a good fit and how other employees feel about the company?
Finding information from the employee perspective is not as simple as other kinds of company research. About.com has written a decent article with some website leads for where to begin looking for employee reviews and company reviews - http://jobsearch.about.com/od/companyreviews/a/companyreviews.htm (it mentions some websites that require a subscription... such as Hoovers. Please check with us before paying for any subscription if you are so inclined, as we have subscriptions to some of these through UHD already).
Another way to look for this information would be to see what news has been published about the company in the recent past. On the Company/Industry resources tab are quite a few databases that are searchable for the latest company news. I would recommend starting with either ABI/INFORM or Business Source Complete (the first two links in the middle of the page).